The invention relates to pipes and tubular conduits, but more particularly, the invention relates to a mandrel and process for making curved hose of specified length with molded ends.
Curved hose is typically manufactured by positioning a pre-cut length of hose carcass over a curved mandrel and then heating and curing the carcass to define a curved hose. The mandrel may have a collar at one end against which the hose carcass is positioned and molded. The open end of the mandrel is usually rounded or "bullet-nose" shape to ease mandrel insertion. The curved hose ends are commonly referred to as "the collar end" and "the bullet-nose end." During cure, the hose carcass may shrink, elongate, or stay substantially the same depending on its construction. These factors must be taken into consideration when establishing the lengths of hose carcass.
A finished hose must have a length that falls within specified tolerances. The irregularity of carcass shrinking and stretching makes it virtually impossible to predict the length of hose carcass necessary to yield a cured hose within acceptable tolerances. Because of this unpredictability, prior art methods involve cutting the hose carcass sufficiently long to yield an over length cured hose, and then trimming the excessive length from bullet-nose end of the cured hose to yield a finished hose of specified length. Additional time and materials are required to trim the hose.